He took up the cudgels against Mr Johnson and had hoped to win a legal battle over the contentious claim which infamously appeared on the side of a pro-leave battlebus.

But he has lost his bid to take the case to the Supreme Court. The High Court had thrown out his case in June - but Mr Ball applied for leave to appeal to the UK's highest court.

However, that appeal was rejected by Lady Justice Rafferty. Despite the apparent setback, Mr Ball was defiant, vowing to continue the fight to bring Mr Johnson to book.

He said:"This isn't over, we are not giving up. We are pursuing it, absolutely."

In a statement, he added: "The offence of misconduct in public office has itself never come before the Supreme Court and is in great need of their attention and clarification."

Marcus Ball Pic Instagram @marcusjball (11447159)

Mr Johnson's lawyers have always argued that there was nothing improperor dishonest about the claim and challenged the case at the High Court.

Mr Ball could still continue his legal battle by applying directly to the Supreme Court, challenging the decision in the European Courts or making another attempt at a prosecution. He had successfully crowdfunded more than £390,000 for legal fees to fight the case.